The Hardest Mate in 2
White to play and mate in 2.
Note: Magnus Carlsen spent almost 2 minutes solving this puzzle.
SOLUTION
The first move is 1. Qa8. If Black plays Qd4, then White responds with Re3#. Otherwise, White plays either Nc5# or Nd6#, so that Black cannot capture the Knight neither with the Rook or the Queen.
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